Sigrid Undset (1882-1949) was a Norwegian-Danish author born in Kalundborg, Denmark. Her best-known work is the historical fiction trilogy, Kristin Lavransdatter, published between 1920 and 1922. The books capture life in medieval Norway from the perspective of one woman, from birth to death. Despite her atheist upbringing, Undset converted to Catholicism in 1924 and most of her following work reflects her strong, religious beliefs. In 1928, Undset won the Nobel Prize for Literature.